MESSAGE sip:alice@example.com SIP/2.0
Via: SIP/2.0/TCP localhost:1234;rport
To: sip:alice@example.com
From: sip:bob@example.com
CSeq: 31415 MESSAGE
Call-Id: bob-and-his-silly-call-random-hex-badc0de-0af123876badef82
Content-Type: text/plain
Content-Length: 6

Hiya
